Sony DSLR-A65 and A77

[gsgary]

Auto Focus Testing - Sony Alpha 77 vs the Canon 5D Mark II in low light | SonyAlphaLab.com

 

[argieramos]

Auto Focus Testing - Sony Alpha 77 vs the Canon 5D Mark II in low light | SonyAlphaLab.com

Okay, so the guy place the subject too close so the a77 advantage for low-light focusing (af beam) wouldn't work and make the 5dMKII looks like it can actually focus in extreme darkness? You're trying too hard Gary. lol

Anyway, why comparing an APS-C to a FF camera? As one of the commenter said, that test was silly..

1. The Canon has over 300% of the amount of light hitting the AF sensors on the Sony due to the translucent mirror setup. Only 30% of the total light is passed onto the AF sensor on A77.

2. Further to this the AF sensor size is relative to the image sensor physically, so more total light passes through the lens onto the AF sensor (what it does with this light is up to the sensor obviously). Comparing full frame to APS-C isn’t really fair in this regard.

3. The sheer number of focus points are not relative to how sensitive they are to light. The more sensors can mean more accurate focusing and focus trackin -- but not low light capability.

4. AF can be more difficult at lower apertures (due to shallow dof causing hunting) and thus why systems need those sub f2.8 sensors for low light. Try comparing them at f4. Also stopping the lens down will not help as the lens is left wide open until taking the shot. Further to this different lenses are better or worse at AF on the same camera – in this instance there are too many variables, the same lens should have been tested on both bodies to make a proper comparison between the AF systems of two very different cameras.

This is enough to show that this is a rather silly test -- unless someone was specifically considering either an APS-C A77 with 16-50 2.8 or a Full Frame 5D Mk II with a 24-105 f4 and wanted to know what the low light focus speed of each was like to make their final decision. Which seems rather specific.

Why not compare it to same level camera from Canon? The 7D..
http://www.popphoto.com/gear/2011/09/lab-test-sony-a77-new-king-aps-c-dslrs
Despite the likelihood that most people will pay more attention to the A77's other features, its autofocus is what really stood out the most in our lab tests. It focused in a mere 0.24 sec at the brightest part of the test and remained under 0.3 sec down to EV 8. At EV 2, which is dimmer than most people's living rooms, the A77 focus in 0.51 sec. And at EV -1, the lowest light level for which the AF system is rated, the camera was able to focus in 0.98 sec.
How does that compare? The EOS 7D was able to focus at EV -2, but at all other light levels in our test, it was slower than the Sony. Nikon's D300s was able to focus in 0.93 sec at EV -1, but as with the Canon, Sony's A77 proved faster at all other light levels.



This proves that 7D AF is really slow in low light.

Correct me if I'm wrong, isn't 7D AF is superior to the 5D MkII?

 

[o hey tyler]

Auto Focus Testing - Sony Alpha 77 vs the Canon 5D Mark II in low light | SonyAlphaLab.com

Okay, so the guy place the subject too close so the a77 advantage for low-light focusing (af beam) wouldn't work and make the 5dMKII looks like it can actually focus in extreme darkness?

How do you place something "too close" for a light to NOT adequately illuminate it? That doesn't even make sense.

 

[gsgary]

Auto Focus Testing - Sony Alpha 77 vs the Canon 5D Mark II in low light | SonyAlphaLab.com

Okay, so the guy place the subject too close so the a77 advantage for low-light focusing (af beam) wouldn't work and make the 5dMKII looks like it can actually focus in extreme darkness?

How do you place something "too close" for a light to NOT adequately illuminate it? That doesn't even make sense.

He is full of excuses

 

[Kolia]

How do you place something "too close" for a light to NOT adequately illuminate it? That doesn't even make sense.

You can see the beam hitting the top of the box while the tester say's he's aiming below at the pencil mark.

We could argue that the AF doesn't even see that beam.

The results are still the same. One camera did focus while the other had a hard time...

 

[argieramos]

How do you place something "too close" for a light to NOT adequately illuminate it? That doesn't even make sense.

Pay attention to the video and what the tester is saying..

"It’s basically focusing with no assist lamp."... So it was a handicap match. lol

7D af is better than the 5D MkII
a77 af is better than the 7D.

It's a fact

 

[argieramos]

He is full of excuses

Which part is the excuse? You are trying too hard. Relax. it's just a camera. nyehehehe!!

 

[gsgary]

How do you place something "too close" for a light to NOT adequately illuminate it? That doesn't even make sense.

Pay attention to the video and what the tester is saying..

"It’s basically focusing with no assist lamp."... So it was a handicap match. lol

7D af is better than the 5D MkII
a77 af is better than the 7D.

It's a fact

Bacause the assist lamp did not shine on the subject don't you think that is a design fault

 

[Kolia]

It a design choice to angle the beam in a way that focusing in the dark at a subject 3 feet away will be compromised.

Why is it compared to the 5D Mk2 anyways ? The price difference is significant !!!

 

[argieramos]

Bacause the assist lamp did not shine on the subject don't you think that is a design fault

With the beam assist, the camera will rely heavily on that to AF. If the tester turned the AF illuminator off, the a77 wouldn't have that issue. Of course you didn't know that. You don't know anything, actually... nyahaha!!
Sorry but no matter what you say , 5D MkII AF will always be inferior to the a77. Not even the superior af of 7D couldn't compete with a77. It's a proven fact....